This invention relates to improved devices for locking cords or other elongated flexible elements against longitudinal movement relative to the device, as for instance in locking a draw string of a garment, laundry bag, or the like.
The locking devices of the present invention are of a general type including a body containing a passage through which a cord or cords extend, and a slide contained within the body and free for limited movement relative to the body along essentially predetermined axis. The passage in the body is tapered in a manner serving to grip the cords between the slide and body walls and lock the cords by wedging action against longitudinal movement in a predetermined direction. Some of the various prior art devices of this general type have been shown in my earlier U.S. Pats. Nos. 3,132,390, 3,861,003 and 3,845,575.
One feature of such devices to which some persons have objected resides in the fact that in prior arrangements of this type the cords have not actually been tightly gripped and clamped against longitudinal movement until a pulling force is exerted on the cords, at which time that force itself may serve to pull the slide axially a short distance within and relative to the body of the device in a relation creating the locking action by the discussed wedging effect. In some instances, it may be necessary to initiate such setting of the locking slide by manually moving the slide axially against the cords and toward the restricted end of the body passage in order to position the slide for properly locking the cords when they are pulled.